// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// Unit tests for event trace provider.
#include "base/win/event_trace_provider.h"
#include "testing/gtest/include/gtest/gtest.h"
#include <initguid.h> // NOLINT - has to be last
#include <new>

namespace {

using base::win::EtwMofEvent;
using base::win::EtwTraceProvider;

// {7F0FD37F-FA3C-4cd6-9242-DF60967A2CB2}
DEFINE_GUID(kTestProvider,
    0x7f0fd37f, 0xfa3c, 0x4cd6, 0x92, 0x42, 0xdf, 0x60, 0x96, 0x7a, 0x2c, 0xb2);

// {7F0FD37F-FA3C-4cd6-9242-DF60967A2CB2}
DEFINE_GUID(kTestEventClass,
    0x7f0fd37f, 0xfa3c, 0x4cd6, 0x92, 0x42, 0xdf, 0x60, 0x96, 0x7a, 0x2c, 0xb2);

} // namespace

TEST(EtwTraceProviderTest, ToleratesPreCreateInvocations)
{
    // Because the trace provider is used in logging, it's important that
    // it be possible to use static provider instances without regard to
    // whether they've been constructed or destructed.
    // The interface of the class is designed to tolerate this usage.
    char buf[sizeof(EtwTraceProvider)] = { 0 };
    EtwTraceProvider& provider = reinterpret_cast<EtwTraceProvider&>(buf);

    EXPECT_EQ(0u, provider.registration_handle());
    EXPECT_EQ(0u, provider.session_handle());
    EXPECT_EQ(0u, provider.enable_flags());
    EXPECT_EQ(0u, provider.enable_level());

    EXPECT_FALSE(provider.ShouldLog(TRACE_LEVEL_FATAL, 0xfffffff));

    // We expect these not to crash.
    provider.Log(kTestEventClass, 0, TRACE_LEVEL_FATAL, "foo");
    provider.Log(kTestEventClass, 0, TRACE_LEVEL_FATAL, L"foo");

    EtwMofEvent<1> dummy(kTestEventClass, 0, TRACE_LEVEL_FATAL);
    DWORD data = 0;
    dummy.SetField(0, sizeof(data), &data);
    provider.Log(dummy.get());

    // Placement-new the provider into our buffer.
    new (buf) EtwTraceProvider(kTestProvider);

    // Registration is now safe.
    EXPECT_EQ(static_cast<ULONG>(ERROR_SUCCESS), provider.Register());

    // Destruct the instance, this should unregister it.
    provider.EtwTraceProvider::~EtwTraceProvider();

    // And post-destruction, all of the above should still be safe.
    EXPECT_EQ(0u, provider.registration_handle());
    EXPECT_EQ(0u, provider.session_handle());
    EXPECT_EQ(0u, provider.enable_flags());
    EXPECT_EQ(0u, provider.enable_level());

    EXPECT_FALSE(provider.ShouldLog(TRACE_LEVEL_FATAL, 0xfffffff));

    // We expect these not to crash.
    provider.Log(kTestEventClass, 0, TRACE_LEVEL_FATAL, "foo");
    provider.Log(kTestEventClass, 0, TRACE_LEVEL_FATAL, L"foo");
    provider.Log(dummy.get());
}

TEST(EtwTraceProviderTest, Initialize)
{
    EtwTraceProvider provider(kTestProvider);

    EXPECT_EQ(0u, provider.registration_handle());
    EXPECT_EQ(0u, provider.session_handle());
    EXPECT_EQ(0u, provider.enable_flags());
    EXPECT_EQ(0u, provider.enable_level());
}

TEST(EtwTraceProviderTest, Register)
{
    EtwTraceProvider provider(kTestProvider);

    ASSERT_EQ(static_cast<ULONG>(ERROR_SUCCESS), provider.Register());
    EXPECT_NE(0u, provider.registration_handle());
    ASSERT_EQ(static_cast<ULONG>(ERROR_SUCCESS), provider.Unregister());
    EXPECT_EQ(0u, provider.registration_handle());
}

TEST(EtwTraceProviderTest, RegisterWithNoNameFails)
{
    EtwTraceProvider provider;

    EXPECT_TRUE(provider.Register() != ERROR_SUCCESS);
}

TEST(EtwTraceProviderTest, Enable)
{
    EtwTraceProvider provider(kTestProvider);

    ASSERT_EQ(static_cast<ULONG>(ERROR_SUCCESS), provider.Register());
    EXPECT_NE(0u, provider.registration_handle());

    // No session so far.
    EXPECT_EQ(0u, provider.session_handle());
    EXPECT_EQ(0u, provider.enable_flags());
    EXPECT_EQ(0u, provider.enable_level());

    ASSERT_EQ(static_cast<ULONG>(ERROR_SUCCESS), provider.Unregister());
    EXPECT_EQ(0u, provider.registration_handle());
}
